The Cross-Cultural Adaptation and Validation of the Persian Version of Dental Discomfort Questionnaire (P-DDQ)

STATEMENT OF THE PROBLEM: It seems essential to detect toothache in children through a validated instrument. Dental Discomfort Questionnaire (DDQ) could specifically detect the behaviors that indicate toothache through parental reports. PURPOSE: Current study aimed to conduct a cross-cultural adaptation process and test the validity and reliability of the Persian version of DDQ (P-DDQ). MATERIALS AND METHOD: In this cross sectional study, 60 children aged 25 to 60 months and their parents who referred to the Pediatric Department of Shiraz Dental School were selected. Parents filled out the DDQ and one examiner recorded the dmft index. To adapt the DDQ questionnaire, conceptual and item equivalence, semantic equivalence and operational equivalence were performed. The dimensions of P-DDQ were evaluated using exploratory factor analysis (EFA). Test-retest reliability and internal consistency assessments were respectively carried out using weighted kappa coefficient (kw) and Cronbach’s alpha. Moreover, the construct validity was evaluated through Mann-Whitney U test and Spearman’s correlation coefficient. Kruskal-Wallis H and Dunn’s post-hoc tests were applied for discriminant validity. RESULTS: The cross-cultural adaptation of P-DDQ was conducted and minor necessary modifications were applied. Test-retest reliability showed moderate and high levels of agreement for DDQ items except for two items. An acceptable internal consistency was observed between DDQ items (Cronbach’s alpha= 0.769). EFA showed that almost all 12 items of the questionnaire were included in three factors. Both construct and discriminant validities were established for P-DDQ. CONCLUSION: P-DDQ was cross-culturally well-adapted, validated, and reliable questionnaire applied with the purpose of detecting toothache among children in Iran.